The best advice I can think of: When airlock bubbling stops, then wait another day or two, then take a gravity reading. Then, wait 3 more days, then take another gravity reading. If the readings changed by exactly zero points, then it is safe to bottle. If the readings changed by one or two points, then it is NOT safe to bottle. Wait another 3 days, then take another reading. When readings stay the same over the course of several days, it is safe to bottle.
In general, it is better to delay bottling for as long as humanly possible. I will typically bottle after 3-5 weeks in primary. This results in better settling of the yeast, better clarity, cleaner flavors, negligible "green"/young off-flavors.
I usually don't do secondary fermentations anymore. You might get a little less yeast sediment in your bottles if you do... or it might not matter at all. It's an extra step that really doesn't buy you much of anything, and might even hurt the beer if done too early. It's not good to remove 90% of your yeast from an actively fermenting beer, as this can result in stalled/incomplete fermentation and increased off-flavors.
Patience is key. Patience. But the 3-day rule above will help you out if you're feeling anxious to get the beer done.
By the way... same goes for kegging. Nice thing with kegs is you don't have a risk of dangerous bottle bombs if you rack it too early.